Video: DePaul University history professor Tom Mockaitis and University of Chicago political science professor Robert Pape join “Chicago Tonight” in discussion.

Could President Donald Trump’s debate stage rhetoric spur violence on election night?

DePaul University history professor Tom Mockaitis said the president’s failure last week during the first presidential debate to recognize – let alone condemn – violent, far-right groups like the Proud Boys could encourage clashes on Nov. 3.

In an op-edpublished last week in The Hill, Mockaitis juxtaposes Trump’s “stand back and stand by” directive to the Proud Boys during Tuesday’s debate with his vehement criticism of far-left radicals and his “refusal to guarantee a peaceful transition” of power, instead advising supporters to watch the polls closely.

“Trump’s failure to openly condemn White supremacy is disturbing in its own right,” Mockaitis writes. “Combined with his repeated refusal to guarantee a peaceful transition if he loses the election, it is deeply troubling.”

On Friday, the Washington Post reportedthe Justice Department and FBI would monitor election night protests and demonstrations to determine whether a federal response is necessary.